[@Cyclone]

Fuso currently hosts Alavian military bases in exchange for training with the Striker units. I'm doubtful they'd sally out and attack people, but fighting near or around them will certain draw them to Fuso's side. Sorta the same deal with Venitium, if fighting gets too close to their borders, expect combat from them.

For the most part, Fuso is in the fight against Izuno alone (mostly because they can keep up such a war by themselves) unless someone else decides to step in